Non-haemorrhagic adverse reactions of oral anticoagulant therapy

Comparative safety review of antithrombotic treatment options for patients with atrial fibrillation undergoing percutaneous coronary intervention

INTRODUCTION

Balancing antithrombotic therapy for atrial fibrillation (AF) patients undergoing percutaneous coronary intervention (PCI) remains a clinical challenge due to coexisting thrombogenic risks. This review emphasizes the delicate balance required to prevent ischemic events while minimizing bleeding complications, particularly in the context of risk assessment.

AREAS COVERED

This review spans from 2010 to October 2023, exploring the complexities of antithrombotic management for AF patients undergoing PCI. It stresses the need for personalized treatment decisions to optimize antithrombotic therapies effectively.

EXPERT OPINION

The evolving evidence supports double antithrombotic therapy (DAT) over triple antithrombotic therapy (TAT) for these patients, showcasing a more favorable safety profile without compromising efficacy. Non-vitamin K antagonist oral anticoagulant (NOAC)-based DAT strategies exhibit superiority in reducing major bleeding events while effectively preventing ischemic events. Recommendations from the 2023 European Society of Cardiology (ESC) Guidelines advocate for NOAC-based DAT post-PCI, endorsing safer antithrombotic profiles.Challenges persist for specific patient categories requiring both oral anticoagulants and antiplatelets, necessitating personalized approaches. Future advances in intravascular imaging and novel coronary stent technologies offer promising avenues to optimize outcomes and influence antithrombotic strategies in AF-PCI patients.

[Vitamin K antagonist-induced necrotic leg ulcer, without protein C and S deficiencies]

INTRODUCTION

Patients treated by vitamin K antagonists (VKA) represent 1% of the population in France. We report a case of atypical necrotic leg ulcers induced by VKA.

CASE REPORT

A 84-year-old woman was referred to our dermatology department because of necrotic leg ulcers that developed for the past 5weeks, and appeared spontaneously after the introduction of a VKA, fluindione. The etiological assessment was non contributive, in particular the search for thrombophilic factors. The skin biopsy found an aspect compatible with pyoderma gangrenosum. The outcome was favorable after discontinuing the fluindione and the switch to apixaban. A complete healing was obtained in 5months.

CONCLUSION

We report an original case of necrotic leg ulcers induced by VKA without deficit of protein C or S, with a pyoderma like histology. Reported cases of ulcers induced by VKA are uncommon and the physiopathology is not well known. The involvement of VKA should be evoked in case of necrotic leg ulcer without specific etiology found.

Oral warfarin intake affects skin inflammatory cytokine responses in rats

Warfarin is an anticoagulant used in prevention/prophylaxis of thromboembolism. Besides the effects on coagulation, non-hemorrhagic reactions have also been documented. Although cutaneous reactions were reported in some patients, the impact on skin immunity was not explored. In the present paper, the effect of 30-day oral warfarin intake on skin cytokine responses in rats was analyzed. Increased release of inflammatory cytokines (TNF, IL-1β and IL-10) was noted by skin explants from rats which received warfarin, but without effect on IL-6. No impact on epidermal cell cytokine secretion was seen, except a tendency of an increase of IL-6 response to stimulation with microbial product lipopolysaccharide (LPS). Topical application of contact allergen dinitrochlorobenzene (DNCB) resulted in slight (numerical solely) increase of TNF release by skin explants of warfarin-treated animals, while epidermal cells responded by increased secretion of all four cytokines examined. The data presented provide new information on the potential of oral warfarin to modulate skin innate immune activity.

Oral warfarin affects some aspects of systemic immunomodulation with topical dinitrochlorobenzene (DNCB) in rats

PURPOSE

The efficacy of topical dinitrochlorobenzene (DNCB) in the treatment of some skin dermatoses is based both on local and systemic effects. It is not known, however, whether it can be applied to patients receiving some other therapy associated with systemic immunomodulation. The aim of the present paper using a rat model was to examine whether oral warfarin (WF) intake, as shown by others and by us, had an immunomodulatory potential to interfere with effects of topical DNCB as systemic immunotherapy.

MATERIALS AND METHODS

Rats received 3.5 mg/l of WF sodium in drinking water for 30 days and were thereafter skin-sensitized with 0.4% DNCB. Changes in the oxidative activity (myeloperoxidase/MPO, reduction of nitroblue tetrazolium/NBT and nitric oxide/NO production) as well as tumor necrosis factor (TNF) production by peripheral blood polymorphonuclear cells (PMN) were measured and compared with PMN from sensitized unexposed to WF rats.

RESULTS

WF intake enhanced some aspects of PMN activity (intracellular MPO activity and unstimulated NO production) as well as their responsiveness to exogenous stimulation (NBT reduction and TNF production from sensitized animals). However, WF also decreased PMN responsiveness of NO production to stimulation. WF affected NO and TNF production solely by PMN, as no effect on these activities of peripheral blood mononuclear cells was seen.

CONCLUSION

Having in mind that polymorphonuclear leukocytes are the most abundant cell type in peripheral blood in humans, increase of basic aspects of PMN activity described in the present paper might be relevant for consideration of using WF as therapeutic modality in patients topically treated with DNCB.

Warfarin-induced leukocytoclastic vasculitis and proteinuria

Warfarin is typically prescribed for patients with thromboembolic diseases and atrial fibrillation. In addition to the complications of bleeding, allergic skin reaction is one of its rare adverse effects. We herein report a case of a 79 year old male patient with leukocytoclastic vasculitis and proteinuria secondary to warfarin. The warfarin was discontinued and oral prednisone therapy was initiated. The cutaneous lesions and the proteinuria resolved thereafter.

Warfarin skin necrosis mimicking calciphylaxis in a patient with secondary hyperparathyroidism undergoing peritoneal dialysis

Warfarin skin necrosis (WSN) is an infrequent complication of warfarin treatment and is characterized by painful ulcerative skin lesions that appear a few days after the start of warfarin treatment. Calciphylaxis also appears as painful skin lesions caused by tissue injury resulting from localized ischemia caused by calcification of small- to medium-sized vessels in patients with end-stage renal disease. We report on a patient who presented with painful skin ulcers on the lower extremities after the administration of warfarin after a valve operation. Calciphylaxis was considered first because of the host factors; eventually, the skin lesions were diagnosed as WSN by biopsy. The skin lesions improved after warfarin discontinuation and short-term steroid therapy. Most patients with end-stage renal disease have some form of cardiovascular disease and some require temporary or continual warfarin treatment. It is important to differentiate between WSN and calciphylaxis in patients with painful skin lesions.

Warfarin-induced purple toe syndrome successfully treated with apixaban

Purple toe syndrome is a recognised adverse effect of warfarin therapy. The literature has described resolution of the ischaemic symptoms on withdrawal of the warfarin and switching to a low molecular weight heparin alternative. We present a case of an 82-year-old man with bilateral blanching vivacious toes and a livedo-reticularis type rash developing 2 weeks after being loaded with warfarin for first detected atrial fibrillation. Vascular surgical review and haematology thrombotic screen did not yield any other pathology and a diagnosis of purple toe syndrome due to warfarin was carried out. The warfarin was stopped and oral anticoagulation started with an oral factor Xa inhibitor, apixaban with resolution of his symptoms. This is the first case report of one of the novel oral anticoagulants being used to treat purple toe syndrome.

Warfarin-induced leukocytoclastic vasculitis: a case report and review of literature

Warfarin is widely prescribed for patients with atrial fibrillation. In addition to unexpected bleeding, allergic skin reaction is one of its uncommon adverse effects. We herein report an 89-year-old man who, after taking warfarin for 4 years, suffered extensive skin eruptions. The skin biopsy disclosed leukocytoclastic vasculitis. The causal relationship between skin lesions and warfarin was confirmed after re-challenge of warfarin. A literature review revealed only 13 such cases reported from 1980 to 2011. Clinicians should be aware of this potential adverse effect of warfarin.

Acenocoumarol and vasculitis: a case report

A 62-year-old woman was referred to the dermatology department for a history of fever, asthenia and cutaneous rash, which appeared after a 3-day course of digitalin and acenocoumarol for atrial fibrillation. The physical examination revealed multiple round confluent purpuric lesions over her entire legs with no blistering. Laboratory exams were all negative. Biopsy of the involved skin was compatible with leucocytoclastic vasculitis. The acenocoumarol treatment was withheld and the skin lesions resolved spontaneously over the next 10 days. The cause of this purpura was seemingly acenocoumarol because of the close temporal relationship between exposure to the drug and the onset of the symptoms, and the spontaneous resolution of the lesions after acenocoumarol was discontinued. This observation illustrates a rare association between vasculitis and acenocoumarol. Clinicians should be aware of this potential adverse effect and recommend interrupting the drug intake when temporal relation is evocative.

Coumarin necrosis induced by renal insufficiency

Cutaneous necrosis is an infrequent complication of coumarin therapy. Skin necrosis has usually been reported in patients with congenital protein C deficiency or, less commonly, protein S deficiency. However, this complication may also occur with acquired and transient protein C and/or S deficiency. In coumarin therapy there is a relatively hypercoagulable state at the start of treatment, and most lesions appear between the third and sixth days. We describe a 75-year-old man receiving coumarin therapy (acenocumarol) for 7 years who was given a nonsteroidal anti-inflammatory agent (diclofenac) for a pain in his knee. Two days later, his renal function deteriorated and skin necrosis became evident. Biopsy showed histological changes consistent with coumarin-induced necrosis. Protein C and S levels were normal. We concluded that in our patient acute renal insufficiency aggravated by diclofenac treatment probably associated with an inadvertent withdrawal could have been the precipitating factor for transient protein C deficiency.

Managing Complications of Anticoagulant Therapy

Understanding the frequency, risk factors, and management of anticoagulant-induced adverse events will assist clinicians in optimizing patient outcomes. The most frequent adverse event of all anticoagulants is major bleeding. Risk factors for major bleeding have been identified with the heparin compounds, the direct thrombin inhibitors (DTIs), fondaparinux, and warfarin therapy. Understanding these risk factors can help prevent bleeding events. For cases of clinically significant bleeding, reversal agents exist primarily for heparin and warfarin. Although less common, nonbleeding adverse events of anticoagulant therapy can also be life threatening. The heparin compounds are associated with the development of heparin-induced thrombocytopenia (HIT) and osteoporosis. HIT can result in life-threatening thrombosis and is usually managed with a DTI. Nonbleeding adverse events with warfarin therapy include skin reactions and the development of venous limb gangrene. Appropriate initiation of warfarin therapy may decrease the risk of venous limb gangrene.

Acenocoumarol-Induced Henoch-Schönlein Purpura

OBJECTIVE

To report a probable case of Henoch-Schönlein purpura associated with acenocoumarol therapy.

CASE SUMMARY

A 76-year-old white woman was prescribed acenocoumarol for chronic atrial fibrillation. Two months after starting therapy, the patient came to our hospital's emergency department because of abdominal pain associated with vomiting. Physical examination revealed multiple round, confluent, purpuric lesions with some vesicles and an area of residual pigmentation. Lesions were present predominantly on the legs and gluteus, and also on the abdomen and arms. Skin biopsy of the lesions was compatible with leukocytoclastic vasculitis with deposition of immunoglobulin A. An upper intestinal endoscopy was done and identified purpuric mucosal lesions in the fundus, body, and antrum of the stomach and the duodenal bulb. Renal function was not affected, although proteinuria (1.26 g/day) was found and microscopic hematuria was observed.

DISCUSSION

The most likely cause of the Henoch–Schönlein purpura in this case was considered to be acenocoumarol because of the close temporal relationship between exposure to the drug and onset of symptoms, as well as the rapid resolution of the symptoms and signs after acenocoumarol was discontinued. The oral anticoagulant was the only identifiable precipitant that the patient encountered before the Henoch–Schönlein purpura developed. An objective causality assessment revealed that the adverse drug event was probable.

CONCLUSIONS

This case report illustrates a probable association between Henoch–Schönlein purpura and acenocoumarol. As of December 2003, this reaction had not been previously reported. Clinicians should be aware of this potential adverse effect of a widely used drug.

Management of oral anticoagulants in the treatment of venous thromboembolism

Venous thromboembolism still represents a major public health problem. After initial heparin therapy, oral anticoagulants are the treatment most often used. Bleeding is the major risk of such a therapy. This review of the literature emphasises the practical aspects of the clinical management of oral anticoagulant therapy, such as initiation, monitoring, interaction, withdrawal, optimal duration, bleeding complications and non-haemorrhagic adverse reactions.

Warfarin induced skin necrosis

BACKGROUND

Warfarin induced skin necrosis is a rare complication with a prevalence of 0.01-0.1 per cent. It was first described in 1943.

METHODS

A literature review was undertaken using Medline; all relevant papers on this rare compli-cation of warfarin therapy were used.

RESULTS

There are several adverse skin manifestations associated with the use of oral anticoagulants, ranging from ecchymoses and purpura, haemorrhagic necrosis, maculopapular vesicular urticarial eruptions to purple toes. This article concentrates mainly on warfarin induced skin necrosis. The syndrome typically occurs during the first few days of warfarin therapy, often in association with the administration of a large initial loading dose of the drug. Although the precise nature of the disease is still unknown, advances in knowledge about protein C, protein S and antithrombin III anticoagulant pathways have led to a better understanding of the mechanisms involved in pathogenesis. Differential diagnosis between warfarin induced skin necrosis and necrotizing fasciitis, venous gangrene and other causes of skin necrosis may be difficult; the disease may also be confused with other dermatological entities.

CONCLUSION

Warfarin induced skin necrosis, while rare, is an important complication. All surgeons should be aware of its existence.

Elective intracoronary Micro-Stent II implantation without quantitative coronary angiography or intravascular ultrasound guidance and without subsequent anticoagulation: short- and long-term results

Intracoronary stenting has been shown to reduce acute closure and restenosis rate in patients treated with coronary angioplasty. The use of high inflation pressures and intravascular ultrasound guidance allowed the substitution of anticoagulants with antiplatelet agents but increased the cost. The aim of this study was to investigate the effectiveness, safety, and long-term outcome of the elective implantation of a relatively new type of stent (Micro-Stent II), without the use of quantitative coronary angiography or intravascular ultrasound guidance and without subsequent anticoagulation. The study included 361 patients who underwent elective microstent implantation. Stent expansion was performed at 8 atm followed by higher inflation pressure at 14-20 atm. Heparin was given intraarterially only once immediately after the arterial sheath insertion. Ticlopidine was started at least 48 hours before the procedure and continued for 1 month while aspirin was continued indefinitely. All patients were followed up for 12.9 +/- 3.6 months. Short term outcome (first month): Stent implantation was successfully achieved in 361 of 366 patients (98.6%). Seven patients (1.9%) were excluded from the study and received anticoagulants because of a suboptimal result. In total, 423 stents were implanted. There was no subacute thrombosis, but acute vessel closure occurred in one patient (0.3%). Non-Q wave myocardial infarction occurred in six patients (1.7%), Q wave myocardial infarction occurred in one patient (0.3%), and only one death (0.3%) of nonischemic origin was reported. No major peripheral vascular complications were observed. Late results: Q or non-Q wave infarction occurred in 13 patients (3.6%), 26 patients (7.2%) underwent a repeat angioplasty, eight patients (2.2%) underwent coronary artery bypass grafting, and four patients (1.1%) died. Overall, 284 patients (78.7%) were free of symptoms, while 77 (21.3%) had recurrent coronary ischemia. In conclusion, Micro-Stent II implantation without quantitative coronary angiography or intravascular ultrasound guidance and without anticoagulation was found to be effective, safe, and with good long-term outcome.